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Care Guide for Forktail Blue-Eye or Furcata Rainbowfish

Many people gravitate towards guppies, platies, and zebra danios sold at major pet store chains because they are small, energetic, and colorful. But if you’re looking for a slightly uncommon fish to liven up your aquarium, let us introduce you to the forktail or furcata rainbowfish.

What are Forktail Rainbowfish?

Pseudomugil furcatus hails from the rainforests of Papua New Guinea, where it is often found in clearwater streams that are teeming with plant life. This 2-inch (5 cm) rainbowfish is known for its glowing blue eyes, yellow fins, and distinct fork pattern on the tail. Because of the yellow tips on their pectoral fins, it almost looks like the fish are waving little pom-poms as they swim around. Like most rainbowfish, the females are less colorful than the males, but we definitely recommend getting 1–2 females for every male. In the presence of females, males display brighter coloration and “spar” with each other in a delightful, circular dance.

furcata or forktail blue-eye rainbowfish

Furcata rainbowfish are known for their yellow “pom-poms” that frantically wave while they swim.

How to Set Up an Aquarium for Furcata Rainbows

This nano fish is quite the speedy swimmer, so set up a 20-gallon aquarium or bigger to give them plenty of room. They enjoy temperatures between 75–80°F (24–27°C), slightly alkaline pH above 7.0, and at least 5° (90 ppm) GH. Rainbowfish tend to swim in the upper half of the aquarium, so an aquarium hood or lid is a must to prevent them from jumping out. Given their natural habitat, consider creating a forest of live aquarium plants for them to explore and swim between.

As a schooling fish, they appreciate being surrounded by as many of their own kind as possible. Fish stores often sell rainbowfish in male-female pairs to make sure that people don’t buy up all the boys, so start with a healthy group of at least three pairs (or two males and four females).

What fish can live with forktail rainbowfish? These happy-go-lucky fish can live with almost any peaceful community fish of similar size, such as corydoras, tetras, and rasboras. However, they may outcompete slow-moving fish during mealtimes, so keep an eye on the food situation to make sure everyone gets a bite. In our experience, they did not bother the adult dwarf shrimp, but they will happily eat any baby shrimp that happens to attract their notice. Also, we have successfully kept Pseudomugil rainbows in community tanks with a betta fish, but it all depends on the betta’s temperament so be prepared to remove him if necessary.

forktail or furcata rainbowfish

Furcata rainbows are very peaceful community fish that do well in planted tanks.

What Do Forktail Blue-Eyes Eat?

These are small fish with small mouths, so aim for a spread of tiny foods that will give them a healthy variety in nutrients. They are not finicky at all and like to eat:

How to Breed Furcata Rainbowfish

Rainbowfish tend to be a bit pricier than your average tropical fish, and Pseudomugil rainbows do not live very long — maybe two or three years. Thankfully, forktail blue-eyes are pretty easy to breed as long as you have both sexes and the fish are not too old. Raise the temperature to around 80°F (27°C) and feed plenty of food to condition them for breeding. Plus, add a DIY yarn spawning mop or large floating plant with long roots (e.g., water sprite) that is easy to remove.

Each male can mate with multiple females each day, which is another reason to get more females than males. Afterward, the females will deposit a few large eggs in the spawning mop or floating plant roots. Try checking the spawning media check every day and move the eggs to a separate fry container with an air stone for hatching. Some hobbyists like to add a few drops of methylene blue to prevent the eggs from growing fungus. Depending on the water temperature, the eggs may hatch in 2–3 weeks. Feed the fry a diet of infusoria, vinegar eels, and powdered fry foods. Once they are large enough, switch them to live baby brine shrimp for fast and healthy growth.

male and female furcata rainbowfish

The two females (above) do not have as much yellow coloration on their fins compared to the male (middle).

Most other Pseudomugil species — such as red neon blue eye rainbowfish (Pseudomugil luminatus) and Gertrude’s spotted blue eye rainbowfish (Pseudomugil gertrudae) — have similar care requirements, so look for the type of nano rainbowfish that strikes your fancy. While we do not ship live fish, you can check out our list of preferred online retailers to see what they have in stock.

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